DEVELOPING DEVICE, IMAGE FORMING DEVICE AND IMAGE FORMING PROCESSING UNIT

摘要

PROBLEM TO BE SOLVED: To provide a developing device, an image forming device and an image forming processing unit by which toner scattering is suppressed and also the deterioration of an image quality such as rear end void is prevented even in the case that the linear velocity of a developing sleeve is raised. SOLUTION: In the developing device which is provided with a non-magnetic developing sleeve 4 which is rotary drivable and a magnet roller 5 to generate a magnetic field by which developer is napped on the developing sleeve 4 at a developing area D opposed to a photoreceptive drum 1 and by which a latent image on the photoreceptive drum 1 is developed by moving and bringing brush- like developer 3 carried on the surface of the developing sleeve at the developing area D in the same direction as the moving direction of the surface of the photoreceptive drum and also at higher speed than that of the surface of the photoreceptive drum, the toner 3a incorporated in the developer 3 is magnetic toner and the attenuation factor of magnetic flux density in a normal line direction generated at the outside of a developing sleeve surface at the developing area D is set >=50%.